1. Field
One embodiment of the invention relates to a loop heat pipe that cools a heat generating component, and an electronic device provided therewith.
2. Description of the Related Art
A loop heat pipe is known as a heat carrier for cooling a heat generating component. The loop heat pipe includes an evaporating section that vaporizes working fluid by heat of a heat generating component; a condensing section that liquefies the working fluid vaporized by the evaporating section; a steam pipe that connects between the evaporating section and the condensing section, and through which the vaporized working fluid flows; and a liquid returning pipe that connects between the evaporating section and the condensing section, and through which the working fluid liquefied by the condensing section flows.
In the loop heat pipe operated in a top heat mode where the evaporating section is positioned higher than the condensing section, the working fluid is accumulated more in the condensing section due to gravity; therefore, making it difficult to supply the working fluid to the evaporating section. Accordingly, the working fluid cannot be circulated, thus the heat generating component cannot be cooled.
Japanese Patent Application Publication (KOKAI) No. 2006-125783 discloses a circulatory heat pipe having a liquid returning pipe provided with a wick that refluxes the condensed working fluid back to the evaporating section by capillary force of the wick. Such circulatory heat pipe is capable of supplying the working fluid to the evaporating section even when the circulatory heat pipe is operated in the top heat mode.
However, when the operation of the conventional circulatory heat pipe operated in the top heat mode is stopped and while the conventional circulatory heat pipe is in non-operation, the working fluid is accumulated on the condensing section side due to gravity. Hence, it is difficult to steadily supply the working fluid when the operation of the heat pipe is restarted so as to supply the working fluid in the wick to the evaporating section. Thus, it is considered to form a wick between the condensing section and the evaporating section through the liquid returning pipe. However, increasing the cross section of the wick will result in loss of capillary force; thereby supply efficiency of the working fluid to the evaporating section decreases.
The invention is provided in view of the foregoing, and it is an object of the invention to provide a heat pipe capable of efficiently cooling a heat generating component, independently of inclination angle of the loop heat pipe, and to provide an electronic device provided therewith.